Abstract

Leslie’s doomsday argument purports to show that the likelihood of the human race perishing soon is greater than we think. The probability we attach to it, based on our estimate of the chance of various calamities which might bring extinction about (a nuclear holocaust, an ecological disaster, etc.), should be adjusted as follows. If the human race were to survive for a long time, we, livingnow, would be atypical. So our living now increases the probability that the human race will end shortly. In this paper, I criticize some attempts to rebut the argument, and present my own. To facilitate the analysis, I consider a structurally similar problem, the “ShootingRoom.”